In a conventional method for managing a wireless channel, virtual carrier sensing is performed by setting, on the basis of information in a received packet, an NAV (Network Allocation Vector) which is a transmission prohibition period. Whether the received packet has been transmitted from a BSS (Basic Service Set) to which a receiver terminal belongs, or a separate BSS adjacent thereto, that is, an Overlapping BSS (OBSS), does not matter. A BBS to which a receiver terminal belongs is referred to as an “own BSS”, and other BSSs are referred to as “OBSSs”.
In addition, a method has been proposed in which NAV management is performed in different manners depending on whether a received packet has been transmitted from an own BSS or an OBSS. A NAV set on the basis of a packet received from an own BBS is referred to as “Intra-BSS NAV”, and a NAV set on the basis of a packet received from an OBSS is referred to as “Regular NAV”.
As a technique for effective use of a wireless channel, Dynamic Sensitivity Control (DSC) has been proposed (which is also referred to as “Spatial reuse”). In some methods using the DSC technique, whether a received packet has been transmitted from an own BSS is determined on the basis of BSS coloring information included in the header of the packet, and a threshold for carrier sensing, that is, a CCA (Clear Channel Assessment) threshold is controlled according to the result of the determination.
The aforementioned DSC may be performed in an environment where an Intra-BSS NAV and a Regular NAV are managed. However, any specific technique for utilizing an Intra-BSS NAV and a Regular NAV in such a case has not been proposed yet.